Low Dose CT

What Is A CT Scan?

CT, or Computed Tomography, uses X-rays to produce detailed three-dimensional images of any part of the body.

Why would my doctor refer me for a CT?

CT scans provide high detailed cross-sectional imaging of your body, bones and vessels. It is commonly used to assess complex fractures, monitor pathology, assess internal injuries such as bleeding and help assess any tumours or blood clots. Your doctor may have referred you for a CT to provide more information following a less detailed exam such as X-ray or ultrasound.

Are there any risks associated with CT?

Your doctor may prefer a CT scan over other modalities such as X-ray or Ultrasound because the image detail is much higher, which allows for a more confident diagnosis.

​The radiation levels for CT scans, while still relatively low, are higher than X-ray and therefore carries more risk. There is no conclusive evidence that the radiation levels used in a single CT scan cause long term health issues, however we always try to limit the amount of radiation a patient receives over their lifetime. In the vast majority of cases, the benefits of having a CT scan (such as your doctor making an accurate diagnosis) greatly outweigh any potential risks.


Some exams require an injection of contrast, in which case there is a small risk of a rection to the contrast media. Before having contrast, you will be required to fill out a questionnaire to assess whether you might be more at risk of a reaction. All contrast CTs are done with a doctor onsite and we have the medication and equipment necessary to treat contrast reactions.

​If you are pregnant, or think you may be pregnant, it is essential that you let our staff know before you have your scan.

Preparation For A CT Scan

Some examinations may require an injection of contrast. Scans that need IV contrast require you to keep well hydrated and eat nothing for 2 hours before your appointment. We may also require some recent blood test results to check your kidney function. If you are diabetic or have a history of kidney disease, please let the receptionist know at the time of booking.

​Scans that do not require IV contrast generally have no specific preparation. The receptionist will inform you of the appropriate preparation at the time of booking.

How long does a CT scan take?

CT scans are usually quick examinations and will take between 5-15minutes.

Do I need to book for a CT scan?

Bookings for CT are preferred, this allows our staff to assess whether or not you require any specific preparation. However, we always accommodate for urgent patients.

Our Machines

Castle Hill Diagnostics is equipped with the latest low-dose CT scanners available on the market. Our scanners are very comfortable for patients of all ages and sizes, and can scan your entire body in a single breath-hold.

​Radiation safety is always our priority. We are highly committed to producing the best possible images at the lowest possible radiation dose. All our scanners are equipped with the latest dose reduction features, which reduces radiation dose by up to 70% compared to similar scanners without these features.

Our radiation doses are well below the recommended levels set by the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA).

If you have any questions regarding charges or would like to know more information, please contact our friendly staff on bookings@castlehilldx.com.au or admin@castlehilldx.com.au. Or directly reach us on Call 02 8660 1400.